Is heat being released or absorbed physical or chemical changes

It can be either. If the object releasing or absorbing heat remains the same but in a different state the change was physical.Like an ice cube absorbing heat and melting. However, heat being released by a burning candle is chemical, as the wick burns and becomes smoke. A chemical change is results in a product with new properties.

the formula for the conversion of temperature from degree celsius to kelvin is:

the sample of water at is converted to kelvin temperature by using the above formula as:

on comparing the two samples of water at or we can say that at and at respectively. the difference between the temperatures of two samples of water is:

hence, one can say that the sample of water at is greater than the sample of water at by .